The most striking feature of magnesium metal relative to other engineering metals is its light weight, especially when viewed in light of its density which is only 1.78 g/cm3, being about 2/9 of steel and ⅔ of aluminum. Magnesium is the lightest metal material which has engineering application value. Moreover, magnesium alloy has a series of advantages such as high specific strength, specific stiffness, good damping performance, and strong radiation resistance, just to name a few. With the continuing to develop electronic products that are light, thin and multi-function, high strength and high thermal conductivity magnesium alloy becomes an important candidate as a structural material.
The structural members of the electronic products are usually complex and precise, therefore the structural members are usually made of die casting alloys. Currently the die casting magnesium alloy in common use is AZ91 series alloy, this kind of alloy has good casting properties and mechanical strength. Its strength can even exceed ZL104 aluminum alloy after aging treatment, so it get to be used widely. However, the thermal conductivity of AZ91 series alloys is only 70 W/(m·K), and is much lower than die casting aluminum alloy which has a thermal conductivity of more than 100 W/(m·K). Therefore, the existing low thermal conductivity magnesium alloy as a component of electronic products greatly affects the electronic products on the requirements of heat dissipation.
In addition, in order to be useful as a structural member in electronic products, the magnesium alloy also needs to have good corrosion resistance, so as to meet the requirements of processing and application. However, there remains an unmet need for improvement of magnesium alloys in this regard.